I would go incognito/private mode on a browser, make a gmail (johnnyfacebook666) and use ot to make a FB (Johnny Robbins Esq. DSc AOM) and then just use the PC to do the browsing in incognito mode.
They can't find out much about you if you're not keeping their cookies and incognito does that. Even use the browser you never use (Safari Mac, Edge Win) to keep em even more separated. You don't need the app for casual FB browsing, it's the thing that will up the level of privacy invasion, and while clunky you can still use the site in browser on mobile in incognito mode.
Facebook totally knows my fake account is me and does nothing, I don't take these precautions but if I needed to that's how I'd do it.